六只脚是国内著名的户外网站，拥有大量的户外GPS轨迹路线，网址为：http://www.foooooot.com/
六只脚是国内著名的户外网站，拥有大量的户外GPS轨迹路线，网址为：http://www.foooooot.com/
搜索关键词岳麓山：
可以发现，每页具有三十个轨迹记录
观察第二页的网址我们可以发现网址为：http://www.foooooot.com/search/trip/all/1/all/time/descent/?page=2&keyword=%E5%B2%B3%E9%BA%93%E5%B1%B1
不难发现其规律：
岳麓山的转义我们不妨测试page为50的情况，在浏览器输入http://www.foooooot.com/search/trip/all/1/all/time/descent/?page=50&keyword=%E5%B2%B3%E9%BA%93%E5%B1%B1：
小结：我们可以通过不断增加page的数字，直至某一页不满足三十个轨迹记录，获取该关键词所有的轨迹记录
点击某个具体的轨迹详情：
可以看到每一页具体的轨迹页面的网址是由轨迹ID构造的，诸如：http://www.foooooot.com/trip/1448263/
从刚才的列表界面我们就可以找到每个轨迹ID：
我们打开浏览器控制台（按F12），点击到网络记录界面，刷新网址：
从网络请求记录中我们发现有两个XHR异步请求其名字很像轨迹数据，点开查看：
可以看到，这个trackjson就是轨迹的JSON数据：
这个footprintsjson就是足迹数据，也就是拍照的那种数据：
对于trackjson，前三列个数据项可以快速判断为时间戳和经纬度，对于后面三个数据项，结合网页数据：
可以判断分别为高程，速度和里程
对于footprintsjson，可以判断前几列数据项分别为时间戳、经纬度、高程、名字、缩略图、详情图，后面几项笔者认为没啥作用
经过上面的数据分析，爬取轨迹数据主要就是通过page和keyword构造网址获取轨迹ID，通过轨迹ID构造地址获取trackjson和footprintsjson
笔者此处基于Python，使用requests库发送http请求，使用Xpath解析界面提取数据
import requests
from lxml import etree
import json
import time
page_num = 1
track_num_arr = []
keyword = "岳麓山"
headers = {'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36'}
page_url = "http://www.foooooot.com/search/trip/all/1/all/time/descent/?page=" + str(page_num) + "&keyword=" + keyword
next_page = True
while(next_page):
response = requests.get(page_url,timeout=5, headers=headers)
tree = etree.HTML(response.text)
trip_list = tree.xpath('//p[@class="trip-title"]/a/@href')
if(len(trip_list) == 30):
page_num = page_num + 1
page_url = "http://www.foooooot.com/search/trip/all/1/all/time/descent/?page=" + str(page_num) + "&keyword=" + keyword
else:
next_page = False
for trip in trip_list:
track_num_arr.append(trip.split('/')[2])
time.sleep(6)
print(len(track_num_arr))
1170
可以看到有1170条轨迹数据
num = 0
for track_num in track_num_arr:
try:
#设置重连次数
requests.adapters.DEFAULT_RETRIES = 5
s = requests.session()
# 设置连接活跃状态为False
s.keep_alive = False
time.sleep(6)
footprint_url = "http://www.foooooot.com/trip/" + str(track_num) + "/footprintsjson/"
trackjson_url = "http://www.foooooot.com/trip/" + str(track_num) + "/trackjson/"
footprint_res = requests.get(footprint_url,headers=headers,stream=False,timeout= 10)
trackjson_res = requests.get(trackjson_url,headers=headers,stream=False,timeout= 10)
try:
trackjson = json.loads(trackjson_res.text)
footprint = json.loads(footprint_res.text)
with open("./trackdata/origin/trackjson" + str(track_num) + ".json","w") as tf:
json.dump(trackjson,tf)
with open("./trackdata/origin/footprint" + str(track_num) + ".json","w") as ff:
json.dump(footprint,ff)
for track in trackjson:
with open("./trackdata/trip_" + str(track_num) + ".txt","a") as tf:
tf.write(str(track[1]) + " " + str(track[2]) + " " + str(track[3]) + " " + str(int(track[0])) + "\n")
with open("./trackdata/all.csv","a") as af:
af.write(str(num) + "," + str(track[2]) + "," + str(track[1]) + "," + str(track[3]) + "," + str(track_num) + "," + str(int(track[0])) + "\n")
num = num + 1
# print("DONE: " + track_num)
# 关闭请求 释放内存
footprint_res.close()
trackjson_res.close()
del(footprint_res)
del(trackjson_res)
except Exception as we:
print(we)
print("ERROR: " + track_num)
with open("./trackdata/error.txt","a") as af:
af.write(str(track_num) + '\n')
# 关闭请求 释放内存
footprint_res.close()
trackjson_res.close()
del(footprint_res)
del(trackjson_res)
except Exception as ce:
print(ce)
time.sleep(60)
Expecting value: line 1 column 1 (char 0) ERROR: 3541376 Expecting value: line 1 column 1 (char 0) ERROR: 3541373 Expecting value: line 1 column 1 (char 0) ERROR: 3541372 Expecting value: line 1 column 1 (char 0) ERROR: 3541371 Expecting value: line 1 column 1 (char 0) ERROR: 3541430 Expecting value: line 1 column 1 (char 0) ERROR: 3505289 Expecting value: line 1 column 1 (char 0) ERROR: 5135959 Expecting value: line 1 column 1 (char 0) ERROR: 3390423 Expecting value: line 1 column 1 (char 0) ERROR: 3389498 Expecting value: line 1 column 1 (char 0) ERROR: 3392149 Expecting value: line 1 column 1 (char 0) ERROR: 3392065 Expecting value: line 1 column 1 (char 0) ERROR: 3392040
ERROR的那几个轨迹确实没有数据在QGIS中利用加载XY文件的方式加载all.csv文件，并设置OSM底图，预览GPS轨迹：
